Tube connection



June 11, 19 c. s. HAWLEY TUBE CONNECTION Filed June 21. 1922 lnve orreference to improvements that are appli-" Patented June 11, 1929.

UNITED STATES CHARLES GILBERT HAWLEY, OF CHICAGO,

ILLINOIS, ASSIGNOR TO LOCOMOTIVE FIRE- IBOX COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE TUBE CONNECTION.

Application filed June 21,

My invention relates to improvements in Nicholson thernnc siphons and has special cable to such siphons as are made of copper, and more particularly the copper siphons which are used in locomotive fireboxes that are made of steel, and therefore present special expansion and contraction problems. A thermic siphon is usually characterized by flanges at its top, which flanges are riveted or otherwise united to the margins of. an opening formed in the crown sheet of the firebox. As a rule the siphon is directly supported by certain of the crown or radial stays of the firebox which are secured directly in the top flanges of the siphon. The fastening of the top of the siphon is there- 'fore not a difficult matter, but when the attachment of the intake neck of the siphon to the throat or fine sheet of the firebox is considered, it is found that the problems present certain ditficulties growing out of the fact that it is inadvisable to attempt to either flange the neck of the siphon and rivet it to the throat sheet or vice versa, and likewise it is inadvisable to attempt to directly weld the copper siphon neck to the margins of any opening that may be formed in the steel fine sheet. The purpose of my invention is to overcome and obviate these particular difliculties. To this end, before placing the copper siphon in the firebox I equip the end of the siphon neck with a steel ring or sleeve. This ring may be heated and shrunk on the copper neck, or, if desired, may be up-set or swedged thereon. In either case, it is so firmly lodged as to form a tight joint with the neck. As hereinafter explained, the sleeve may be left free to move on the neck or the neck within the sleeve, or the sleeve may be riveted or patch-bolted to the copper neck. Thus equipped with an armored neck the siphon may be hoisted or otherwise positioned in the firebox and the armored neck then placed in an opening in the throat or flue sheet of the latter, and thereupon I directly unite the steel sleeve with the margins of the opening of the steel sheet by means of a progressively applied autogenous weld. The heating of the sleeve in the course of the progressive weld is not sufficient to loosen it on the siphon neck, but even if that should occur it is an easy matter to afterwards calk the joint which is presented between the differing metals, and thus 1922. Serial No. 570,039.

it is assured that with a little attention the joint can be kept tight at all times.

My invention will be readily understood on reference to the accompanying drawings, which form part of this specification, and in which Fig. 1 is a vertical longitudinal section of a steel firebox containing a copper siphon embodying my invention. Fig. 2 is a cross-section thereof. Fig. 3 is an enlarged sectional detail of the throat portion of the boiler illustrating this present invention. Figs. 4 and 5 illustrate slight modifications of the structure shownin Fig. 3.

In the drawings I have depicted a locomotive firebox of a very common form which presents a steel throat sheet 2. \Vithin the firebox I have shown a pair of so-called thermic siphons S, S, same being substantially triangular water walls which receive water from the front water space or throat 4 of the boiler and deliver the heated water and steam into the boiler space 5 above the crown sheet 6 of the firebox. \Ve are not here especially interested in the detailed construction of the copper siphon, other than to note that the intake neck portion S thereof is of tubular form and penetrates the water space 4, being accommodated in an opening in the steel plate 2. As before mentioned, I equip the end of the neck S with a heavy steel ring 7, making sure that the ring fits the neck so tightly as to form a water and steam tight joint therewith. This ring I then attach to the sheet 2 by means of a progressively applied autogenous weld 8.

Sliding movement between the siphon neck and the sleeve 7 may, if desired, be prevented by means of a number of patch-bolts or rivets 9. These bolts or rivets may be positioned either in the fire space or in the water space of the firebox, or in both, as indicated in Fig. 5.

I apprehend that the better method of attachment between the ring 7 and the copper neck of the siphon will be found to be the simple construction shown in Figs. 1 and 4,'which is no wise differs from Figs: 3 and 5 except in the omission of the patch-bolts or rivets, the neck being left free to slide or slip within the ring. If desired, the extreme end S" of the siphon may be belied out as. shown in Fig. 4. In this connection it may be,noted that in all forms of my invention the siphon is directly supported from the Wrapper or shell of the boiler as by means of the radial stay-bolts 10 appearing in Figs. 1 and 2. If the slip form of connection shown inFigs. 1 and 4 is employed rigid stay-bolts may be employed in the. throat of the boiler, but if the rigid connection of Figs. 3 and 5 is employed it is better that the stay-bolts adjacent thereto shall be of the flexible type and backedoiflto permit a free breathing movement of the throat or flue sheet 2 wherein the neck is secured.

Having thus described my invention, I

claim as new and desire to secure by Letters Patent:

In combination with a steel firebox sheet having an opening therein, a copper tubular member having an end extending through said opening, and a steel ring lodged upon the end of said tubular member and autogenously Welded to that portion of the steel firebox sheet defining said opening, the end of said tubular member being left free to slip within said steel ring.

In testimony whereof I affix my signature.

CHARLES GILBERT HAWLEY. 

